Related art radio tags may include a radio communications circuit having first and second terminals coupled to a loop antenna, and a first conductor forming a first curved face provided with a first end part and a second end part opposite to the first end part. The first end part has a third terminal connected to the first terminal, and the second end part has a first area. Such radio communications tags may further include a second conductor forming a second curved face provided with a third end part including a fourth terminal connected to the second terminal. The second curved face has a fourth end part opposite to the third end part, and the fourth end part has a second area. The first area and the second area are overlapped in parallel to each other, and the first curved face and the second curved face form the loop antenna (e.g., Patent Document 1).